21251914 has 4 divisors (see below), whose sum is σ = 31877874. Its totient is φ = 10625956.

The previous prime is 21251903. The next prime is 21251929. The reversal of 21251914 is 41915212.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 17766225 + 3485689 = 4215^2 + 1867^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5312977 + ... + 5312980.

Almost surely, 2^21251914 is an apocalyptic number.

21251914 is a deficient number, since it is larger than the sum of its proper divisors (10625960).

21251914 is a wasteful number, since it uses less digits than its factorization.

21251914 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10625959.

The product of its digits is 720, while the sum is 25.

The square root of 21251914 is about 4609.9798264201. The cubic root of 21251914 is about 276.9912285927.

The spelling of 21251914 in words is "twenty-one million, two hundred fifty-one thousand, nine hundred fourteen".